Cover Story: Charlotte's dirty air

CHARLOTTE, NC (WBTV) - Yes, it's dangerously hot outside.  But the air quality on Tuesday really was not all that bad.

For all the code orange ozone days we've had lately, Tuesday didn't meet that threshold.

Air temperature and air quality don't necessarily go hand in hand.

Charlotte has had 13 Code Orange Ozone days so far this summer (since the first of April which is the start of ozone season.)   But Tuesday was not one of them.  Why not?

And do you know you live in one of the smoggiest cities in America?  How's that?

Smoggy skies are what we're used to seeing in Charlotte when the heat turns up and the humidity kicks in and the forecast goes to Orange.  But there was none of that on Tuesday.

Meteorologist Kelly Franson explains why.

"To get ozone you actually need the sunlight interacting with the chemicals," she said.

The sun came out late in the afternoon but for the most part most of the day was spent in the clouds.

Sure it got hot, 100-degrees in some places.

And it was humid, extremely oppressive to work in but a gentle breeze and the clouds hiding the sun kept the air from becoming stagnant and heating up as much as it normally does when we have a problem with ozone.

"Heat can speed up that process but it's the sunlight that really gets it going. On a cloudier day you don't tend to see that reaction as much," said Franson.

Ozone forms when pollution from cars and trucks and from smokestacks releases pollutants into the air - nitrogen oxides and volatile organic compounds react to create ground level ozone..

And sunshine really gets it going.

Ozone is invisible what we see on smoggy days is the particulate matter.

This spring the American Lung Association rated Charlotte tenth on its list of Top 10 Smoggiest Cities.  Charlotte was the only city on the list east of the Mississippi.

Outside Charlotte and Houston, Texas the rest of the cities are in California.

"Everybody in our region needs to understand that they are living in a region of the country that has poor air quality many days in the summer," says June Blotnick with Clean Air Carolina.

She says Charlotte's geography plays a big part in why ozone is so quick to form here in the summer but people also are major contributors.

To get at that the non-profit advocacy group two years ago got federal grant money to retrofit almost 90 local school busses to make them pollute less.

And it's encouraging companies to get signs - encouraging drivers to "turn off the engine" - not to idle cars for long periods in the summer time.

"We have a responsibility one because we should care about our health.. and two because we play a role in this. We have control over pollution," said Blotnick.

Doctors like to say ozone is sunburn on the lungs when it gets into your lungs it does damage.

Children, the elderly and those with asthma are particularly susceptible to the effects of ozone.

We have had 13 Code Orange Days so far this summer.  We're on par to exceed last year's number which was 17.

Two weeks from now the EPA is expected to release new ozone standards - a stricter standard for ozone to better reflect its impact on public health.

Some of the days in the past that have been Code Orange - may in fact become Code Red under the new standard.

The North Carolina Division of Air Quality is forecasting a Code Orange Day for Wednesday.

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